The present application is based on and claims priority from Japanese Patent Application 2001-12178 filed Jan. 19, 2001, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to an AC generator for a vehicle such as a truck or a passenger car.
2. Description of the Related Art
Recently, an AC generator has become more compact and more powerful in order to be mounted in an engine compartment that has narrowed to meet demand for more spacious and comfortable passenger compartment.
U.S. Pat. No. 5,998,903 discloses one of compact and powerful AC generator in which a plurality of conductor segments is mounted to increase power and to improve cooling performance thereof. However, it is difficult for such an AC generator to provide different number of turns or segments to meet various specifications for various kinds of vehicles.
JOURNAL OF DENSO TECHNICAL DISCLOSURE No. 125-040 discloses a compact and powerful vehicle AC generator that aims at solving the above problem. However, it is still difficult to accommodate connection wires that connect a plurality of segments in a limited space.
Therefore, a main object of the invention is to provide an compact and powerful AC generator that can easily provide a different stator winding to meet various specifications.
According to a feature of the invention, a vehicle AC generator comprises a stator winding including star-connected three phase winding groups of a plurality of phase windings. Each of the three phase winding groups is comprised of series-connected two pairs of the phase windings that are 30 degree different in phase from each other. Each pair is comprised of a pair of the phase windings that is 180 degree different in phase from each other and series-connected by a first connection segment, and the two pairs are series-connected by a second connection segment. Each phase winding comprises a plurality of U-shaped conductor segments, each of which has a turn portion and a pair of inclined portions having connection ends. The stator winding includes a first coil-end group in which a plurality of the turn portions is disposed and a second coil-end group in which a plurality of pairs of the inclined portions is disposed. The first and second connection segments for the same phase winding group are disposed together and are separated from those for different phase winding groups.